HcN13, a Fibroblast Growth Factor Binding Protein, Is Associated with Shell Formation in Hyriopsis cumingii.

Fibroblast growth factor binding proteins (FGF-BPs) are involved in bone formation by binding to FGFs and modulating FGF signaling in vertebrates. Herein, a novel shell matrix protein gene, HcN13, was identified from the mussels Hyriopsis cumingii. Sequence analysis indicated that HcN13 belongs to the FGF-BP1 family.

HcN57, A Novel Unusual Acidic Silk-Like Matrix Protein from Hyriopsis cumingii, Participates in Framework Construction and Nacre Nucleation During Nacreous Layer Formation.

In the classic molecular model of nacreous layer formation, unusual acidic matrix proteins rich in aspartic acid (Asp) residues are essential for nacre nucleation due to their great affinity for binding calcium. However, the acidic matrix proteins discovered in the nacreous layer so far have been weakly acidic with a high proportion of glutamate. In the present study, several silk-like matrix proteins, including the novel matrix protein HcN57, were identified in the ethylenediaminetetraacetic acid-soluble extracts of the nacreous layer of Hyriopsis cumingii.